Ledger clamp



Dec. 6, 1932,

v T. H. KINGSTON LEDIGEQR CLAMP Filed Dec. 13, 1928 N D-ST Patented Dec. 6, 1932 TES THOMAS H. KINGSTON, or

PATENT? wn srn soMEnvILLE; massnonosn'rmshssieivon ro. 31111115;

. Ens PATENT scAFFoLnmeooMrANY, A. PARTNERSHIP comosnn or mane.

KINGSTON, A. R. KINGSTON, o. c. IPIMM, AND

AT wnszr SOMEBVILLE, MASSACHUSETTS MABEL e. grrcnmv, DOING 'nnsmEss;

Application filed December 1a, 928. :seunno. 3253178;

This invention relatesto builders scaffold-J ings and in particular to clamps for-securing the ledger boards to the poles, the ledger. boards being the horizontal boards placed edgewise vertically, -for=the supportof the flooring of the scaffolding. These clamps are of greatlimportance because upon the secur ity'oftheir hold depends the safety ofpersons and lives of human beings. Consistent with their importance, they should be capable" of easy and quick application and removal in the interest of diminishing as much as possible the cost of erection and taking down.

the scaffolding. Accordingly, an important object of the invention is to provide a construction of clamp whichwill combine/the properties of complete security In the drawing Fig. lis a perspective view scaffolding showing. the application of a ledger board clamp embodying my invention. Fig. 2 is a vertical section'thereof; a

Fig. 3 is a horizontal section on the line 33-of Fig. 2;

Fig. 4 is a view in side elevation of another embodiment of the invention;

Fig. 5 is a perspective fragmentary view of still another embodiment of the invention Fig. 6 is a perspective fragmentary view of another-embodimentof my invention;

The several embodiments of myinvention shown in the drawing are found inconstructions which include what,-for convenience will be termed a main or body member in the form of a bar that, when applied to the scafi'olding, extends vertically across the outer face. of the pole, and/two hook-form jaws pivoted to said body at the upper andlower ends thereof, and adapted to reach.

across Or straddle the ledger board and hook over or overlap the ledger board at the top and bottom edges respectively, and a screw applied at the vertical center of the body'for exerting clamping pressure against the outer the ends of adjoining ledger at thepole,

is the quick and easy adaptation ofthe clamp. to single or double thicknesses ofZ-l'edger together to provide and easy and I pivotally held-as by means ,of a pin-or rivet '12,- passing through aliningholesin theisi'de" of a portionof.

member.

side of the pole. Ledger board clamps are applied to a single thickness of board and also at times'to a double-;thickness-{as when boards overlap and 'a feature of the invention boards without dependence upon adjustf mentof the clampscrew.

- The body member, 10, is made "of a lengthy or piece of channeliron, the web of the chan nel being cut away at top andj'bottom and the side flanges bent or broughttowardseach I.

other and extended parallel], 'sufiiciently close jaw, 11, as the case may be, such jaw being plates and thejaw end. p l p The lower j aw, although freejto swing upward towards the body membelg is limited so th'atit will not swing substantially horizontal position, and a' stop device of some sort is provided which will preventit moving below the horizontal -posi forfthesnug fitting be- 7 tween themof the end of the upper or lower below a horizontal or tion or one at right angles'tothe bodymem ber. Such stop may be simply a lug,1'3,- pro jecting from its bottom edge which will cn-' counter the adjacent inner edge of the body" Thus, when the Workman isapf" plying the clamp to the scaffolding the lower bar when swung down to horizontal position is'in its proper'position to have its inner or hooked end' engage-the ledger board and the workman thus does not; have the inconvenient job of swinging it to and holding it in such horizontal position. The upper'qaw has no such stop device, but is free to swing through a large range and, of course, when the clamp is placed in position with the lower bar'e xtending beneaththe ledger board, it isfa sim ple act for the workman to 'sw'ing the topfba'r over, above the top edge of the ledger board,

allowing it to drop into its proper position with its inner hooked end overlapping, the

'in'n'er'side' of the ledger board at th'etop.

3 As itis desirable, to havethe channel made 7 91? as light metal aspossibldlglprovide-a re- 1 inforcing bar or's'trip, 14, of metalfwliicli isi.

Q riveted to the channel web preferably on the I inner side'at-the central portion thereof longitudinally, and such reinforcingv bar or strip has a central hole that alines with a hole in said web, both holes being threaded for-the clamp screw, 15. Thus the reinforcing bar providesextra material to give an extended engagement between the clamp screw and'the V I body member. Thus reinforced, the channel is given all needed strengthto resist-tendency to buckle under the pressure exerted thereagainst'when the clamp screwengages at its I j inner-end the outer side of the scaffolding pole. At the inner end ofthe clamp screw, 15,

' is swiveled a pole engagingplate, 16, of sub stantially larger area. than. the end of the screw so as to reduce the un-itgpressure on the pole. ,Said pnmgae, is ,no' wider than the distance between the Channelfl'anges, so that thereby protected from damage.

it may be-placed within-the channel and As has already been indicated,f0verlapped orv spliced ledgerboards present 'a double thickness for engagement by-th'e clamp.j To take care of the diflerence :in thickness be-- tween a single ledger board-and two ledger boards,manipulation of the screw would be atedious, slow operation. I, therefore, provide in certain embodiments of my invention jaws to deal with either a single thickness-of the jaws with means which will enable the ledger boards .ora' double, thickness; .As

' shown-in Figs. and 2,-thi's means may take member. Each jaw in this case,.c0nsists-0f i that 'by moving'theshank carryingethe pins the form of'a two-part jaw whichis adjust able as to length so that thehooked end-may be placed further from or nearer to the body two overlappingshanks, one pivoted to the other. One shank has a longitudinally ex distance between two adjoining slots,ol8,iso

to play back and forth in the 'slots, -it;-may be shifted to place thej aw into either of the two} desired positions inwhich it will be firmly Z 7 held underthe clamping pressure.

As'shown in Fig.4, instead off-a. single 2 hook adjustable to different positions, there maybetwohooks adapted for alternate use.-

These may be two jaws, 20, ofdififerent length both secured by the same pivot,

i t d two-j awarrangemenmthe short jaws not in use are swung .out ofthe way, but not. the longjaws when the short are used. The parts designated, respectively," 130, 1 50 and 160 in 4 are similar to-the partsjdesig-j Q nated, respectively, 13,15 and-16 in Fig;

ig-i 5., ,i W,... 0, h t

1'. ...As. shown in 120-, to *the' 7 body member, 100, as shown; Wi;th the;

Besides the advantages mentionedof-the pivotal connection between the aws and the j body member, there is thefurther advantage of folding or collapsing the clamp into a compact space for storageor handling;

Of course, other clamplng means i 70, than a screwfmaybe employed. For example, a f cam arrangement maybe used as shown in Fig; 6, where a cam or ec'centrlc, 2I,1s mount ed oni a'pivotpin, 22,;journaled in the side --flangesi of the'member, '10, with a handle, 23,

that projects through a vertical slot in the web for easy manipulation. The cam or.

-eccentric, 2l, .maybear directly upon'the outer side of the pole, or as shown in 6,;1t may engage the end of ashank, 24,01. a poleeengaging plate orshoe, 25,theshank,

-'2t, being"supported and guided by a hole in a cross bar or strap, 26,. riveted to: the side flanges of the'member, 10.1 l

I The channelfo'r theibody' thus is specially advantageous foruse of the cam clamp-as it thereon and as the reaction pressure falls on the side flanges edgewise, and onab oth, ample resistance to buckling is had.

9 What I claim is 7 I a A ledger board: clamp having'jaw means and a body member consisting offa channel.

having a web and flanges,a'reinforcingplate.

enables. the latter readily to be mounted at' midlength for the channel and a clamp I screw said: plate andiwebhaving alin'ed threaded holes through: which-said screw passes, the'fianges'of the channel. at opposite ends being benttowards"eacliother and saidjaw. means having shanks pivoted between such ends.

' 2. Aledger board clamp comprising a body member, jaws and clamping means applied i to the body membergsaidbody member consistingof a channel having side flanges bent at their ends towardseach other and means attaching the aws tosaidbent ends. '1

cally extending 'body'and j aw members pivoted to the body, at vertically-spaced apart points, at least one of the -j aw members-being limited to swing between .a substantially horizontal position and a vertical position; and coacting. parts on said body and :the, jaw h- 3. A ledger board clamp 'having ai-verti member which isglimitedto swing between asubstantially horizontal position and a vertlcal position that contact when said jaw memberis'in a substantially horizontal-posi tion, the jawuportiionsof the jaw'memb'ers extending vertically'when in ledger board clamping position. v

In testimony whereof I; hereunto aflix my signature; 1 v

I THOMAS H. 

